Problem: Simplify the following expression: ${4(3+7n)-4(-3n+4)}$
Explanation: Distribute the ${4}$ into the first set of parentheses: $ {4(}\gray{3+7n}{)} - 4(-3n+4) $ $ {12+28n} - 4(-3n+4) $ Distribute the ${-4}$ into the parentheses: $ 12+28n {-4(}\gray{-3n+4}{)} $ $ 12+28n + {12n-16} $ Rewrite the expression to group the ${n}$ terms and numeric terms: $ {28n + 12n} + {12 - 16}$ Combine the ${n}$ terms: $ {40n} + {12 - 16}$ Combine the numeric terms: $ {40n} {-4}$ The simplified expression is $40n-4$